from machine import Pin
from time import sleep

led1 = Pin(5, Pin.OUT)
led2 = Pin(18, Pin.OUT)
led3 = Pin(19, Pin.OUT)
b1 = Pin(25, Pin.IN, Pin.PULL_UP)
b2 = Pin(14, Pin.IN, Pin.PULL_UP)
b3 = Pin(13, Pin.IN, Pin.PULL_UP)

while True:
    n1 = b1.value()
    n2 = b2.value()
    n3 = b3.value()
    n = 3 - (n1 + n2 + n3)
    if n == 1 :
        led1.value(1)
        led2.value(0)
        led3.value(0)         
    elif n == 2 :
        led1.value(1)
        led2.value(1)
        led3.value(0)
    elif n == 3 :
        led1.value(1)
        led2.value(1)
        led3.value(1)
    else :
        led1.value(0)
        led2.value(0)
        led3.value(0) 
    sleep(0.1)